Question

I have the following segment of a java file:

Integer x; Integer y; Face facing;

enum Rotate { Clockwise, Anticlockwise };

enum Face { East, North, West, South };

and am having trouble figuring out how to implement a function to change the Face of an object (i.e. the direction that the object is facing).

The function begins as follows

private void rotateIt(Rotate rotateIt) {
    {

I have begun using the switch statement as follows ( below text is inside braces above ):

switch (facing)
case North  : ...?;
case West   : ...?;
case East   : ...?;
case South  : ...?;

I’d like to use the Clockwise enumeration to turn it from East to South etc. and Anticlockwise to do the reverse IYGWIM.

Answer 1

switch (facing) {
  case North  : facing=rotateIt==Rotate.Clockwise?Face.East:Face.West; break;
  case West   : facing=rotateIt==Rotate.Clockwise?Face.North:Face.South; break;
  case East   : facing=rotateIt==Rotate.Clockwise?Face.South:Face.North; break;
  case South  : facing=rotateIt==Rotate.Clockwise?Face.West:Face.East; break;
}

I should get a large percent of your grade retroactively!